Electron Configurations and basic Period Table

Electron Configuration

Valence Electrons - All Electrons in the out most energy levels

Oder of Sub Shell Configuration - not needed for Grade 9

• PEL-principle Energy Level(neighbourhood)

• Sub Shell level (house)

• Orbitals (room)

Periodic Table

Superficial

• atomic number

• groups and periods

Deeper

• blocks

• electron configuration

• chemical and physical properties

Periodic Law

At regular but varying intervals, elements show a general repletion of properties due to their electron configuration

Monotonic versus diatomic Atoms

Monatomic - exist as one atom and is happy, can be found alone

Diatomic - never are alone in nature → most halogens → can be memorised with BrINClHOF or 7up

Classes of Elements

Metals

• good conductors of electricity and heat

• malleable → hammered into thin sheets

• ductile → able to be a wire

• have lusture →shiny

• tend to loos electrons therefore being cations

Non Metals

• poor conductors

• brittle

• tend to gain electrons

• anions

Alkali Metals

• Li, Na, Rb, Cs, Fr

• highly reactive, especially with water

• always found combined in nature

Transition Metals

• variable ionic charge - due to electron configuration

• widly used

• have many different properties

Halogens

• most reactive non metals

• show trends in colour and phase as STP (standard temperature and pressure)

• only group wizth solid liquid and gas

Noble Gasses

• very unreactive

• non metals